Any chef knows how handy Williams Sonoma is. Though their prices are decidedly not cheap, they WILL have what you're looking for, be it a cooking utensil or special spice. For me, it's primarily a browsing store, but be sure to check out their seasonal sales and featured tastings. My personal suggestion is to try out their flavored dipping oils.
Parking is at a premium on the street, so I suggest parking in the nearby garage on Chicago Ave. and walking over.